iSmaRT: imaging small renal tumours

  • Research type

    Research Study

  • Full title

    Dual source CT assessment of ablation success in small renal tumours

  • IRAS ID

    236002

  • Contact name

    Vicky Goh

  • Contact email

    vicky.goh@kcl.ac.uk

  • Sponsor organisation

    King's College London

  • ISRCTN Number

    ISRCTN15730405

  • Duration of Study in the UK

    2 years, 11 months, 31 days

  • Research summary

    Nephron-sparing treatments have become the standard of care for T1 renal masses. Ablative therapies are a safe alternative to partial nephrectomy with 5-year recurrence-free & cancer-specific survival rates of 95.2 & 99.4% respectively & better preserve renal function. In patients undergoing ablative therapy it may be a challenge to confirm complete ablation (analogous to complete surgical resection). Current practice is the assessment of CT attenuation change pre- & post-therapy. Attenuation of >10 Hounsfield Units (HU) in an area of nodular or crescent-shaped irregularity is considered suspicious for persistent disease. However it is well-known that HU is variable as it is dependent on multiple factors including scanner, underlying tissue contrast, contrast agent dose, administration rate & cardiac output. Indeed peri-procedural studies have shown that small foci of disease are often missed. Thus there is a need to improve peri-procedural assessment & detection of residual disease/early recurrence, allowing earlier intervention in this small but relevant subgroup of patients.

    Our systematic review of perfusion imaging following ablation of renal tumours (search date: 23/05/2017) only identified 4 studies (using dynamic contrast enhanced MRI, arterial spin-labelling MRI, perfusion-CT (CTp) & dual energy-CT respectively (DECT); 3 prospective; 90 patients total); a limitation was the lack of gold-standard, low number of recurrences & study heterogeneity; no studies compared DECT with CTp, highlighting the need for further prospective studies in this clinical setting.

    Our study aims to investigate whether dual source computed tomography (DSCT & CTp) quantification of vascularisation pre & day 1 post-ablation improves the assessment of residual disease versus complete ablation & predict for early recurrence in renal cancer? Secondarily, we investigate whether DECT iodine mapping can be used interchangeably with CTp parametric mapping in this context. Finally, for a subgroup of 10 patients, we will perform an additional CTp on Day 14 to investigate the ideal timing for perfusion imaging.

  • REC name

    London - City & East Research Ethics Committee

  • REC reference

    18/LO/2005

  • Date of REC Opinion

    22 Jan 2019

  • REC opinion

    Further Information Favourable Opinion